Cyclic phosphonitrilic halide, especially the chloride, and particularly the cyclic trimeric and tetrameric phosphonitrilic chloride species are of interest for their use as intermediates for agriculture chemicals, as intermediates for fire retardants, as coatings for ceramics and metals, and in the preparation of polymers having unique glass transition point, solvent resistance, and high and low temperature properties. Of particular interest are polymerized high purity cyclic trimers and tetramers. Hoses, for example, automotive and industrial gaskets, seals, and lubricants are very useful product forms of polymerized high purity chlorophosphazenes. Conventional processes employed for the preparation of phosphonitrilic chlorides or chlorophosphazenes, such as the reaction of phosphorus pentachloride and ammonium chloride, usually produce a mixture of polymers consisting of (a) cyclic phosphonitrilic chloride polymers (PNCl.sub.2).sub.n where n is an integer of 3 or more and (b) linear or open chain PNCl.sub.2 chains end-blocked with the elements of phosphorus pentachloride of the probable formula (PNCl.sub.2).sub.n.PCl.sub.5. Problems have arisen in obtaining the cyclic polymers, particularly the aforementioned trimeric and tetrameric species, relatively free of higher cyclic and linear polymers and in a highly purified form such that the trimeric and tetrameric species can be polymerized into a gel-free benzene or toluene soluble polymer, hereinafter referred to as polygrade material. Although several methods of purification are available, a good degree of purification to date has been difficult, if not impossible to achieve. Specific prior art methods of purification involve the extraction of chlorophosphazene from petroleum ether solutions with sulfuric acid, U.S. Pat. No. 3,008,799; controlled crystallization in variety of solvents, U.S. Pat. No. 3,378,353; separation of the trimer and tetramer from the produced mixtures through distillation involving a spinning band column, U.S. Pat. No. 3,379,510; contacting molten chlorophosphazenes with an inert solvent vapor so as to selectively vaporize the cyclic trimer polymer, separating a solvent vapor phase laden with trimer and some tetramer from the molten polymer residue, condensing it to form a solution of trimer and tetramer in the solvent and subsequently recovering trimer together with some tetramer from the solution, U.S. Pat. No. 3,677, 720; steam distillation of chlorophosphazenes resulting in hydrolysis of n=4-9 and hence separation of trimer, Chemical Abstract, volume 77, Page 540, 159648 D (1972) and saponification and hydrolysis of chlorophosphazenes by treatment with aqueous sodium of ammonium hydroxide resulting in unreacted trimer and tetramer, U.S. Pat. No. 3,694,171. Other methods disclosed include separating substantially pure trimer from a mixture comprising tri-(phosphonitrilic chloride) and at least one higher polymer thereof by contacting the mixture with a liquid monohydric alcohol at a temperature and a period of time sufficient to cause the higher polymer to pass into the liquid phase of the alcohol while leaving tri-(phosphonitrilic chloride) in the solid state, U.S. Pat. No. 2,862,799; treating a mixture of phosphonitrillic chloride polymers in an organic solvent at a temperature in the range of 75.degree. C.-100.degree. C. with water so that a major portion of the linear polymers are segregated to an aqueous phase and a major portion of the cyclic polymers are segregated to an organic phase, U.S. Pat. No. 3,669,633; treating a crude mixture of cyclic and linear phosphonitrilic chloride polymers with petroleum ether in which the cyclic polymers are soluble whereas the linear polymers are not, and thereafter the insoluble polymers are separated, after which the polymer solution is separated into a vapor phase of petroleum ether and a solid phase of cyclic polymers of phosphonitrilic chloride, U.S. Pat. No. 3,367,750; and passing a hot inert gas through a molten mixture of crude phosphonitrilic chloride polymers, contacting the thus produced phosphonitrilic polymer-laden gas with an inert solvent to produce a solution of polymers in said inert solvent, and afterward separating the solvent from said solution by conventional means to obtain trimer and tetramer cyclic phosphonitrilic chloride polymers U. S. Pat. No. 3,372,005. U.S. Pat. No. 3,952,086 discloses a process for the purification of crude chlorophosphazene by adding a Bronsted base to a vessel containing crude chlorophosphazene, removing water fromed in the vessel from the reaction of Bronsted base with the impurities in crude chlorophosphazene and then removing at least a very high purity cyclic chlorophosphazene trimer. According to the disclosure, the chlorophosphazene so formed can be polymerized in a gel-free benzene soluble polymer i.e. polygrade material.